fix nightly ci

Author: guschmue

tests/test_backend.py

@@ -82,7 +82,8 @@
     quantize_and_dequantize = tf.compat.v1.quantization.quantize_and_dequantize
     resize_nearest_neighbor = tf.compat.v1.image.resize_nearest_neighbor
     resize_bilinear = tf.compat.v1.image.resize_bilinear
-    resize_bilinear_v2 = tf.compat.v2.image.resize
+    if LooseVersion(tf.__version__) >= "1.14":
+        resize_bilinear_v2 = tf.compat.v2.image.resize
     is_nan = tf.math.is_nan
     is_inf = tf.math.is_inf
     floormod = tf.floormod